Clinical progression, disease severity, and mortality among adults hospitalized with COVID-19 caused by the Omicron and Delta SARS-CoV-2 variants: A population-based, matched cohort study

Zitta Barrella Harboe* (Member of study group), Casper Roed (Member of study group), Jon G. Holler (Member of study group), Fahim Iqbal Khan (Member of study group), Aya Nihad Abdulrahman Abdulrahman (Member of study group), Stefan Lundby Mulverstedt (Member of study group), Betina Lindgaard-Jensen (Member of study group), Barbara Bonnesen Bertelsen (Member of study group), Christian Søborg (Member of study group), Thyge Lynghøj Nielsen (Member of study group), Line Vinum Hansen (Member of study group), Birgitte Lindegaard Madsen (Member of study group), Andrea Browatzki (Member of study group), Mads Eiberg (Member of study group), Peter Haahr Bernhard (Member of study group), Emilie Marie Juelstorp Pedersen (Member of study group), Gertrud Baunbaek Egelund (Member of study group), Arnold Matovu Dungu (Member of study group), Adin Sejdic (Member of study group), Inger Hee Mabuza Mathiesen (Member of study group)Naja Z. Jespersen (Member of study group), Pelle Trier Petersen (Member of study group), Lars Nielsen (Member of study group), Micha Phill Grønholm Jepsen (Member of study group), Thomas Ingemann Pedersen (Member of study group), Robert Eriksson (Member of study group), Hans Eric Sebastian Seitz-Rasmussen (Member of study group), Morten Bestle (Member of study group), Henrik Andersen (Member of study group), Ulrik Skram (Member of study group), Mads Rømer Skøtt (Member of study group), Sarah Altaraihi (Member of study group), Pradeesh Sivapalan (Member of study group), Jens Ulrik Stæhr Jensen (Member of study group), Kristian Bagge (Member of study group), Kristina Melbardis Jørgensen (Member of study group), Maja Johanne Søndergaard Knudsen (Member of study group), Thomas Leineweber (Member of study group), Uffe Vest Schneider (Member of study group), Magnus Glindvad Ahlstrom (Member of study group), Sofie Rytter (Member of study group), Nina Le Dous (Member of study group), Pernille Ravn (Member of study group), Nanna Reiter (Member of study group), Daria Podlekareva (Member of study group), Andreas Knudsen (Member of study group), Stine Johnsen, Lars Erik Kristensen (Member of study group), Cæcilie Leding (Member of study group), Bastian Bryan Hertz (Member of study group), Thomas Benfield (Member of study group), Ole Kirk (Member of study group), Sisse Rye Ostrowski (Member of study group), Sigurdur Thor Sigurdsson (Member of study group), Anders Perner (Member of study group), Nikolai Kirkby (Member of study group), Martin Schou Pedersen (Member of study group), Maarten Van Wijhe (Member of study group), Lone Simonsen (Member of study group), Peter Michael Bager (Member of study group), Tyra Grove Krause (Member of study group), Marianne Voldstedlund (Member of study group), Lasse Engbo Christiansen (Member of study group), Marc Stegger (Member of study group), Arieh Cohen (Member of study group), Anders Fomsgaard (Member of study group), Jannik Fonager (Member of study group), Rebecca Legarth (Member of study group), Morten Rasmussen (Member of study group), Sophie Gubbels (Member of study group), Jan Wohlfahrt (Member of study group), Troels Lillebæk (Member of study group), Caroline Klint Johannesen (Member of study group), Thea K. Fischer (Member of study group)

*Corresponding author for this work
2 Citations (Scopus)

Abstract

Background To compare the intrinsic virulence of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) omicron variant with the delta variant in hospitalized adults with coronavirus disease 2019 (COVID-19). Methods All adults hospitalized in the Capital Region of Copenhagen with a positive reverse transcription polymerase chain reaction test for SARS-CoV-2 and an available variant determination from 1 September 2021 to 11 February 2022. Data from health registries and patient files were used. Omicron and Delta patients were matched (1:1) by age, sex, comorbidities, and vaccination status. We calculated crude and adjusted hazard ratios (aHRs) for severe hypoxemia and mortality at 30 and 60 days. Results 1,043 patients were included. Patients with Omicron were older, had more comorbidities, were frailer, and more often had three vaccine doses than those with Delta. Fewer patients with Omicron developed severe hypoxemia than those with Delta (aHR, 0.55; 95% confidence interval, 0.38 0.78). Omicron patients exhibited decreased aHR for 30- day mortality compared to Delta (aHR, 0.61; 0.39 0.95). Omicron patients who had received three vaccine doses had lower mortality compared to Delta patients who received three doses (aHR, 0.31;0.16 0.59), but not among those who received two or 0 1 doses (aHR, 0.86; 0.41 1.84 and 0.94; 0.49 1.81 respectively). Similar findings were observed for mortality at 60 days. Similar outcomes were obtained in the analyses of 316 individually matched patients. Conclusions Among adults hospitalized with COVID-19, those with Omicron had less severe hypoxemia and nearly 40% higher 30- and 60-day survival, as compared with those with Delta, mainly driven by a larger proportion of Omicron patients vaccinated with three doses of an mRNA vaccine.

Original languageEnglish
Article numbere0282806
JournalPLoS One
Volume18
Issue number4
ISSN1932-6203
DOIs
Publication statusPublished - Apr 2023

Keywords

  • Humans
  • Adult
  • SARS-CoV-2/genetics
  • COVID-19
  • Cohort Studies
  • Patient Acuity
  • Hypoxia
  • Disease Progression

Fingerprint

Dive into the research topics of 'Clinical progression, disease severity, and mortality among adults hospitalized with COVID-19 caused by the Omicron and Delta SARS-CoV-2 variants: A population-based, matched cohort study'. Together they form a unique fingerprint.

Cite this